A professional radon mitigation system for a typical house can usually be installed in one day (National Radon Program Services, Kansas State University). The work is a hole through the floor, a pipe, a fan and some sealing, but the details decide whether it works. This guide walks through the process and what changes if you do it yourself. For how the system works, see how radon mitigation systems work.
The process, step by step
The Minnesota Department of Health lays out ten steps (MDH):
Before
- A radon test shows the home has a problem (confirmed at 4 pCi/L or more).
- You contact mitigation professionals and ask for bids.
- Each one walks through the home to plan the system.
- You go over your questions with them and ask for a written proposal.
- You compare bids and pick one.
During
- The installer may run diagnostic tests to choose the fan size and where the suction point goes.
- Cracks and openings in the basement are sealed.
- The system is installed: a suction hole through the slab with a small pit dug beneath it, PVC pipe, the fan, the exhaust above the roof edge, and a gauge or alarm.
After
- The installer explains how the system works and how to look after it, and gives you written instructions and warranties.
- You retest the home to make sure radon has come down.
What the installation involves
For a slab or basement floor, at least one 4- to 6-inch hole is drilled through the concrete, a small pit is dug out underneath, and PVC pipe is inserted and run to a fan that creates suction below the slab. One pipe is often all a house needs (Kansas State University). The pipe can run inside the house or up an outside wall, and it ends above the edge of the roof (MDH).
EPA’s installation standards set rules that you can check on the finished job (EPA, Radon Mitigation Standards; EPA, Consumer’s Guide):
- Pipe joints are permanently sealed, and the pipe slopes so rain and condensation drain back to the ground below the slab.
- The fan is outside, in the attic or in a garage with no living space above it, never in the basement, the living space or a crawlspace.
- The fan is mounted to limit vibration and fitted with removable couplings so it can be replaced later.
- The exhaust is above the roof, at least 10 feet above the ground and 10 feet from windows and doors, unless it is at least 2 feet above them.
- Electrical work follows local code. In Minnesota, for example, most installs need an electrical permit (MDH).
- A gauge or alarm shows whether the system is working, and the system is labeled.
The follow-up test
Test again within 30 days of installation, but no sooner than 24 hours after the fan starts. A 2- to 7-day test with windows and doors closed is recommended. EPA suggests an independent test, by you or a separate tester, as well as any test by the installer (EPA, Consumer’s Guide).
Do you need a licensed installer?
It depends on your state. Among the six states where we publish full county data:
| State | Mitigators must be licensed or certified? | Source |
|---|---|---|
| Colorado | Yes | Colorado DORA |
| Iowa | Yes | Iowa Admin. Code 641-44 |
| Minnesota | Yes | Minn. Stat. § 144.4961 |
| Pennsylvania | Yes, for anyone paid to mitigate | PA DEP |
| Michigan | No; the state recommends NRPP or NRSB certification | Michigan EGLE |
| Wisconsin | No; the state recommends NRPP or NRSB certification | Wisconsin DHS |
Elsewhere, your state radon program can tell you the rules and give you a list of qualified contractors. Where a state doesn’t regulate radon work, EPA suggests hiring someone with a national certification (NRPP or NRSB) who follows an installation standard such as ASTM E2121 (EPA, Consumer’s Guide).
Doing it yourself
Kansas State University’s radon program notes that some homeowners do fix their own homes (sosradon.org). EPA and Pennsylvania’s DEP still recommend a qualified contractor, because without the right equipment and knowledge you could raise your radon level or create other hazards. If you do it yourself, both say to get training information and EPA’s technical guidance from your state radon office first (EPA, Consumer’s Guide; PA DEP).
The risks to plan for:
- Backdrafting. A fan pulling air from under the house can affect fuel-burning appliances such as a furnace or water heater. EPA’s standards say an active system can’t be installed until any backdrafting is fixed (EPA, Radon Mitigation Standards).
- Fan placement. The fan goes in an unconditioned space such as the attic, the garage or outside, to keep radon from leaking back into the home (MDH).
- Exhaust placement. An exhaust too low or too close to a window can send radon back inside.
- Electrical work and permits. These follow local codes, and some places require a licensed electrician.
- Proving it worked. Always do a follow-up test.
Cost
Costs depend on the house, its foundation and the local market. State programs report typical ranges of about $500 to $2,000 in Pennsylvania, averaging $1,000 (PA DEP), and $1,500 to $3,000 in Minnesota (MDH). See radon mitigation cost for more.